Roller-bearing ankle joint for artificial limbs



W. A. MCELROY ROLLER BEARING ANKLE JOINT FOR ARTIFICIAL LIMBS Filed Nov.'7, 1925 Jam.` 8, 1929.

l Patented Jan. 8, 1929. n

AUNITED STATES 1,698,372; f PATENT oFFlcn.

WILLIAM A. MCELRCY, or `SAN FRANCISCO, CALIFQRNIA.

ROLLERjB-EARING ANKLE JOINT FOR ARTIFICIAL LIMBS.

Application filed November 7, `1923. Serial No. 673.272.

joint which may be packed with lubricant, to eliminate the necessity ofperiodic oihng as is vthe case at the present time.

A still further object ofthe invention is to provide an adjustableroller bearing ankle joint for artificial limbs that will be superior inpoint of simplicity and inexpensive in construction, positiveness inoperation.

e'iciency, as contrasted with devices of a similar character. Otherobjects and advantages will appear as this description progresses.

In this specification and the annexed drawings, the invention isillustrated in the form considered to be the best, but it is to beunderstood that the invention is not limited to such form, because itvmay be embodied'- in other forms, and itis also to be understood that inand by the claim following the description, it is desired to cover theinvention in whatsoever form it may be einbodied.

In the accompanying one sheet of draw- ,inse

through an ankle joint constructed in accordance with my invention.r Y jFig. 2 is an end elevation of Fig. 1.

Fig. 3 is a cross-section .through a moditied form of ankle joint.

Fig. et is across-section through a. further modified form of anklejoint.

in the foot l for the purpose of receiving' facility and convenience inuse and general Fig. 1 represents a vertical cross-section In detail theconstruction illustrated inv an attaching nut 6 for fixedlyl locking'thebase l and shank 5 on theJ- foot 1. The base l is provided with va `pairof spaced standards and 8 on the opposite sides thereof each of whichhave aligned holestherethrough. 7 is of smaller diameter-than the hole10 through the standard 8, said hole-'10 being .threaded to receive apivot pin 11.r l

The pivot pin 11 is tapered, the smaller end thereof being threaded topass through rIhe hole 9 through the standard l the hole ,9 in thestandard 7v and to be engaged by a lock nut 12 on the outside face ofsaid standard 7. rlhe larger end of the pivot pin is threaded to engagethe tapped l opening 10 inthe standard 8, and a lockv nut 13 is adaptedto engage said end of the pivot pin.y By loosening the lock. nuts 12 and13 the pivot pin 11 can be rotatedA in its bearing supports in thestandards vand 8 to impart an endwise or axial movement thereto. Upontightening the lock nuts 12L and13 the pivot pin 11 would remain in afixed position until again re-adjusted. The end of the pivotppin 11 isslotted `as atll to receive a screw-driver when it is desired to obtainlengthwise movement of said pivot` pin11.rj

A casing 15 having a tapered hole thereanl ythrough is arranged aroundthe shaft 1,1,

said casing 15 being of a length approximately the same as the shank ofthe pin be-y tween the inner faces of the standards 7 and 8, VThe casing15 is provided with a shank. 16 thereon which is adapted to be securedto the lower end of the calf section 2 of the artificial limb. Aplurality of rollers 17 are interposed between ythe tapered pivot pin 11and the interior face of thehole through the casing 15.

A bearing formed such as described would have the space around therollers 17 between the pivot pin 11 and casing 15 packed with lubricantand `under ordinary usage should not require attention during the lifeof th'e artificial appliance. In the event that usage would produce wearon or betweenv the contacting bearing surfaces it would only benecessary to back up the nuts 12 and 13, move the pivot pin l1 forwardto overcome the lost motion, and then tighten the nuts 12 and 13. Thus,a very simple and effectively constructed ankle joint is `quire nolfurtherattention and which is also.l

` described. i In 3,"a pivot pin^21 is prol vided constructed asiadouble cone, one end -provided with means whereby looseness or lostmotion may be quickly and easily com,`

.Twan axial inovementfofthevcasing 15 relative u to the bolt 40 whichwould eliminate play` pensated for.` A r i In the modified form ofinvention shownV in Fig. 3, the `operation of the invention issubstantially the same as that heretofore of thefpivotpin 21 l'beingthreaded at 19 Vfor engagement withV a lock nut 22jonf"the outsidefofthestandard 7. The opposite f lflarger end Vof the pivot pin is threadedor i engagement' With `a lock nut 23 adapted to bemoved into andfromcontact with the "outer faceoflthestandard 8. Two setsfof rollers 27wouldlbe interposed between the opposite conefaces" oi the `pivot pin 21and the hole through the casing 25, and casing Wouldbe `secured to thecalf sect-ion 201i the artificial limb.

In the modification shown in Fig. 4 "I `provide a base 4, asin Fig. 1,having the rev spective side standards 7 and 8, A bolt 4() passesthroughthe respective standards 7 and 8 andA a lock nut 41 `is applied to anend of the bolt 40 for lockingV said bolt tightly in position ybetweenthe said. standards 7 and 8. Acone shaped or tapered pivotfpin 42` ismounted on the" shaft 40, said pivot pin 42 beingfof a `shorter lengththan the dis! `tance between the saidstandardsf: and 8.

` One end'otthe pivot pin 42 isthreaded to receive anattachingnut 43 anda casing 15 is mounted aroundthe pivotpin 42 between thestandards 7andattaching nut 43.1 i Roll ers y47 are-arranged between the pivotpin42 )and casinglwhich would `be" infimersedV in lubricant, the same as,describedinFig.

1. In the event that play would occur fbgstandards; apivot one end belng1nv t readed engagement with the binding nut 4 3 to beV rotated, causingor looseness betweenthe contacting lbearing parts. After the desireddegree of move- .inentlvvould be obtained, the loclrnut 41` would vbetightencdtohold theV assemblyin f the desired relation.; The modifiedforms ot the invention shown "in Figs. `3 and 4,

while structurally different `from that shown in Fig. 1,`are"essentiallythe sameinvention Vfunctioning to produce lthe same niodeof operation.

`Having thus what I claim and desiretosecu're by Letters An adjustableVbearing `for artificial fliinbs comprising a frame having opposite side1pin'ha-ving threaded ends,

one standard and havingbearing support in the `opposed standard,saidpivot pin having a tapered bearing portion intermediate thestandards and adjustable axially thereber tween; loclr nuts on thethreaded ends of the" `pivot pin to be impingedfagainst the standardstosecure' the tapered-bearing portion 7 0` in adjusted posit-ion; acasing havingy a described this invention,

taperediboreto receive the tapered bearing portion of the pivotA pinjandrollersfinterposedjbetween thetaperedbore of the `cas-A ing and the,taperedbearing' portion of the l i In testinionywhereof, Iihavehereunto set l my hand at San Francisco, California, this pivot pin.

'lsthfday` of October, 1923,?

\ V WILLIAM A.. MQELROY.

